Trimmer for phonograph-records.



J. DQROCKHILL. TRIMMER FOR PHONOGRAPH RECORDS. A$PLIUATION FILED AUG. 4,1909.

974,435. Patented Nov. 1, 1910.

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.,, J'OHN.DAVID ROCKHILL, OF CONRAD, IOWA.

TRIMMER FOR PHONOGRAPH-RECO RDS.

Specification of Letters Patent.

Application filed August 4, 1909.

Patented Nov. 1, 1910.

Serial No. 511,229.

' To all whom it may concern:

' tion.

My invention is designed to be used in the nature of an attachment thatmay be readily, quickly, and easily attached to or detached from anordinary phonograph in place of the cylindrical frame that-contains thereproducing instrument.

My object is to provide a trimming device of this kind, of simple,durable and inexpen sive construction that may be readily and quicklyadjusted to trim off the records to any depth of cutde'sired; and, morespecifically, it is my object to provide a cutting tool of such shapeand size as to trim a phonograph record without chipping or breaking therecord, to thereby properly prepare a record for use in such a mannerthat is surface is well adapted for receiving impressions.

Myinvention consists in the construction, arraingement, and combinationof the various parts of the device, whereby the objects contemplated areattained, as hereinafter more fully set forth, pointed out in my claims,and illustrated in the accompanying drawings, in w'hich-- Figure 1 showsa central, sectional view of a device embodying my invention, thecutting tool being shown in engagement with a portion of a phonographrecord. Fig. 2 shows a sectional view on the line 2 of Fig. 1, and Fig.3 shows a perspective view of the frame for holding the trimming tool.

Referrim to the accompanying drawings, I have used the reference numeral10 to indicate the supporting frame of the trimming device. Thissupporting frame preferably cylindrical in shape and comprises a bodyportion 10 with a flange 11 at its top. The said body portion ispreferablv made of the same size and shape as the body portion of theframe that holds the reproducing instrument of the phonograph with whichthe device is to be used. In this connection, it is obvious that by theuse of a frame of this kind, the operator may readily and easily removethe reproducing instrument from a phonograph and then place the frame ofthe trimming instrument in the position formerly occupied by thereproducer, and then theother parts of the phonograph may be operated inthe ordinary way and the trimmer will operate to prepare a phonographicrecord for use. In this way the expense of a separate instrument forturning the record and advancing the trimmer is dispensed with.

Pivoted to the under surface of the body portion 10 is a disk 12 havinga projection 13 at the side opposite from the pivotal point, whichprojection is placed in a guide loop 14 connected to the body portion 10to thereby limit the lateral movement of said disk. Seated in the bodyportion 10 is an adjusting screw 15 having its lower end designed toengage the disk 12 to limit its forward movement. Connected to thecentral portiop of the disk 12 is a contractible coil spring 16 attachedat its upper end to a sup )ort 17 connected to the body portion, so tiatthe said .disk 12 is yieldingly held upwardly againstthe adjusting screw15.

Fixed to the disk 12 is a block 18 having the cutting tool 19 a pliedthereto. This cutting' tool is extended downwardly and in a directiontoward the hinged end of the disk 12, the angle of the end surface ofthe cutting tool being such that it will form an acute angle relative tothe nhono aph record with which it is to be used, as c earlyillustratcd'in Fig. 1 of the drawings. The body portion of the cuttingtool at the lower end thereof is approximately round n cross section, asclearly illustrated in l 2, and the end thereof is arranged at an an leslightly deviating from a vertical line, with the lower portion inclinedaway from a vertical line in a direction toward the bodyof the cuttingtool, as clearly shown in'Fig. 1.

The portion of the phonograph record.

shown is indicated by the reference numeral 20 and the direction of itsmovement relative to the cutting tool is indicated by an arrow in Fig.1; that is to say, the end of the cutting tool is so shaped that it willform an acute angle relative to that portion of the phonograph recordwith which it is used which is traveling in a direction toward thecutting tool. The diameter of the cutting tool at its end is greatly inexcess of the width of the spaces between the various spiral lines onthe record over which the reproducing instrument passes so that witheach operation of the cutting tool, a number of spiral lines on therecord are covered, and

inasmuch as the cutting tool travels in the same path as the reproducinginstrument, it

' is obvious that the various paths which the .cutting tool makes willoverlap each other and this will result in producing a finished recordcomparatively smooth and even.

In practicalgnse and assuming that it is desired to trim'a record, theoperator simply detaches the body portion of the frame that ,containsthe reproducing instrument and substitutes for it the body portion 10 ofthe "trimming device. Then the record is placed onjthe mandrel ofthephonograph and the i phonograph is operated in the ordinary way.

'Byhaving the end of the cutting tool rounded oil-its lower surface, itis obvious that H 'whenkit cuts into the'record, it will not have sharpcorners that would tend to chipor breakout portions of the record withwhich it comes in contact. Furthermore, by having the end of thecuttingtool inclined at an acute angle relative to that portion of therecord which is moving in a direction to-' ward it, the cutting toolwill tend to scrape the record as distinguished from cutting the record,and there will be no tendency for the cutting tool to chip or break outthe portions of the record with which it comes in contact as "would bethe case if the cutting end of the tool were arranged at an obtuse anglerelative to the part of the record that was moving toward it. Therounded lower edge 'of the tool, together ,With the scraping operationwhich. it accomplishes, makes it possi ble for the device to operatewith a minimum of applied power, hence the power of an ordinaryphonographic instrument is sufiicient to operate the trimmer. By means,of the adjusting screw, the depth to which ing the phonographicreproducing instrument, a disk pivoted at one edge to the urn dersurface of said body portion, an adjust ing screw mounted in the bodyportion to engage the free end of the disk for adjusting its positionrelative to the body portion and for holding it away from the body, aspring connected to the disk and extended through the body portion toyieldingly hold the disk upwardly against said adjusting screw, and acutting tool fixed to the under surface of the disk substantiallycircular in.

cross section and extended at an acute angle relative to the centralportion of the disk, the cutting edge of said tool being substantiallyround and being inclined at an angle slightly less than a right anglerelatively to the lower surface of the cutting tool, for the purposesstated.

2. A device for trimming phonographic records, comprising asubstantially circular body portion designed to be detachably sup-"ported in a phonographic instrument in placeof the circular frameusually employed for supporting the phonographic reproducing instrument,a disk pivoted at one edge to the under surface of said body portion andhaving a projection at its opposite edge, a guideloop ,fixed to the bodyportion to receive said projection, an adjusting screw mounted in thebody portion to engage said disk, a contractible spring fixed to thecentral portion of the disk and extended through said body portion, asupport for said spring fixed to the body portion, and a cutting toolfixed to the under portion of the disk substantially circular in crosssection and extended at an acute anglerelative to the central portion ofthe disk, the cutting end of said tool being substantially round andbeing inclined at an angle slightly less than a right angle relativelyto the lower surface of the cutting tool, for the purposes stated. 7

Des Mgines, Iowa, J uly 15, 1909.

JOHN DAVID ROCKHILL.

Witnesses:

WM. A. SANDOE, E. W. SCHWIELERT.

